Wire stripping machine



Oct. 24, 1933.

w. s. ROTHERHAM Re. 18,978

WIRE STRIPPING MACHINE Original Filed May 8, 1930 ZSheets-Sheet l on N OCL'24, 1933. w s ROTHERHAM 'Re. WIRE STRIPPING MACHINE Original Filed May 8, 1930 2 Sheets-Sheet 2 3&6 QW

Reissued Oct. 24, 1933 WIRE STRIPPING MACHINE Walter S. Rotherham, Bloomingdale, N. J., as-

signor toE. I. du Pont de Nemours & Company, Wilmington, Del.,,a corporation of Delaware Original No. 1,882,947, dated October 18, 1932,

Serial No. 450,799, May 8, 1930.' Application for reissue August 19, 1933. Serial No. 685,971

9 Claims. (01. s1 9.51).

Thisinvention relates to an improvedprocess.

of and machine for removing combustible coverings, such as insulation and the like, from electric wires, and more particularly to a process 5 and machine for burning and stripping insulation from the ends of insulated conductors and the like. p e I In the preparation of insulated wires for use in the manufacture of certain articles such as '10 detonators and the like, it has been the practice to cut or burn a groove in the insulation by electric means a short distance from one end at a time and then remove the insulation from the groove to the end of the wire for convenience in connecting to the detonators or for short-circuiting the ends.

The processes or machines heretofore proposed for this purpose have had the disadvantage that if the insulation was-removed from conducting wires by cutting means the wires themselves were nicked or out, causing them. to be easily broken in subsequent operations. There is the further 1 disadvantage'that byusing such a cutting means, or by burning a groove in the insulation by means of an electrically heated element, the insulation has a tendency'to unravel and besides causes frayed ends. I

'An object of the present invention is to overcomethe. disadvantages of prior processes and 30 machines for removing insulation from conductor wires.

,A' further object ofthis invention is to remove insulation from conductor wires by a process capable of large scale production with economy in time and labor. 1

A still further object of my invention is to strip the insulation from conductor wires in such a manner that the ends of the insulation are even and firm so asto facilitate subsequent operations.

toproduce the most desired product with the.

least amount of labor and handling of the wires. With thisend in' view my process and apparatus contemplates that a multiplicity of the wires be subjected to the various essential operations for this purpose' at the same time. 7

According to my invention a multiplicity oi the wires may be subjected to the burningaction and automatically to the stripping means simul- Other objects will appear as the description taneously. In this manner great economy in operation, labor, and production results.

As a-more specific embodiment of my invention,

and without limiting it thereto, my invention may be described morespecifically as follows:

Figure 1 illustrates the plan view of the preferred embodiment of my invention.

Figure 2 is a sectional-view, taken on line 2--2 of Figure 1, of the wax impregnating tank through which the wires are drawn, together with a sectional view of the clamping or retaining means carried by the carriage. Y

Figure 3 is a side view, taken on line 3 3 of Figure '1, of the conveyor means and shows a clamp engaging wires in place and a-second clamp from which the stripped and treated wires are being removed.

' Figure 4 is a view taken on line 4-"401? Figure 1 and illustrates the means for shellackingor' otherwise treating the ends of the insulated wires from which portions of the insulation havebeen removed, and I Figure -5 shows the stripping means which-en gages the portion of the insulation to be removed."

Figure 6 represents the retainingor clamping means 18, shown in Figure 3, and-consists of two members operated by the lever 18a, having an eccentric which forces the two plates to the position shown in Figure '7, thus gripping and holding the wires;

Figure 7 illustrates the clamping plates in their wire grippingand holding position. Figure 8 illustrates in greater detaila slotted cross-head or scotch yolk, well known in the art, which operates the fingers shown in Figure 5.--

I preferably draw 'a number of the wires across a table or other plane surface, engage the wires as a single unit by a clamping or gripping means,

at each end of the desired lengths, cut oif the I wires, transfer the unit, consisting for example '95 of 12 wires, with the clamping or retaining means engagingthe wires a short distance from the ends, insert the clamping or retaining means in grooves in the table whereby the unit is conveyed across the surface of the table by chain conveyor or .100 9 other conveyor means. Asthe wires are conveyed automatically across the table the ends are subjected to the step of removing the'insula-'- tion from a short length of the wires near their ends. This is done by first passing the'wires over a narrow fiame," or other heating means, which plays upon each of the wires as they are conveyed laterally across the table. This operation burns a section of the insulation around each of the wires. The wires passthen through the cally strip the insulation from the burned or charred section to the ends of each of the wires.

The wires are then passed through a coating solution, whereby the ends of the insulation remaining on the wires are properly coated to prevent fraying in subsequent operations. This coating material may be shellac, varnish, or the like and may be automatically sprayed upon. the

ends of the unremoved insulation or the ends maybe passed through an automatic feeder such as is used in the dispensing of liquids.

It will be understood that variations and modifications may be made in the process and apparatus without departing from the spirit or scopeof my invention.

wires as they are drawn from the spools or reels with an impregnating-material to complete an important step incthe manufacture of. the insulated wires previous to cutting the wires in the proper lengths before removing the insulation from the ends.

- Inthe accompanying drawings the numeral 1 represents a number of I insulated .wires drawn from spools or reels ,or the like supported on a rack or frame adapted to support a, largenumber of similar spools or reels of the insulated. wire so that a multiplicity may be in use atone time with a reserve at hand. The numeral 2 represents a wax impregnating tank through which the insulated wires are drawn. This tank 2 may be heated by any suitable means, so as to keep :the waxfifor example paraffin) in solution. The

insulated wires arethen drawn from'the tank 2 through a wiper 3 which removes anylsurplus wax from-thewires and then overs roller by means of-a carriage 7. This carriage movesion rollers labackahdlforth across a raisedsurface' of the 'table B bymeansof the air ram 10 This ram 10 is controlled by an operator by means of the car'- riage operating valve 8 and .lever 8a,.- The carriage "7 is adaptedby means vof the clamping means 6 to engagethe ends of the insulated wires as they protrude through stationary clamping means 4, and cutting means'or shear 5 operated by the lever 5a. Upon operation of the valve 8 the ram draws the carriage across the table to the position shown in dotted lines. Clamping means 18. are then inserted over the wires at each end so as to engage them in spaced relation in the clamping means. The stationary clamp 4 engages and holds the endsof the wires extend- ,ing from the reels while the severed pieces with their retaining or clamping means 18 are transferredto the conveyor; the shearing means severs the wires, and the operator releasesthem from the clampingmeans 6. The clamping means with the group. of wires retained therein are then placed in the grooves 19.and 20 of table B and narrow'flame at 12 which burns a narrow section subiected'to the action of the stripping means 14..

are engaged by the conveyor chain 11,'the wires extending across thetable in the position shown in Figure I of the drawings. The conveyor chainsf carry the'ends of the wires across the of. the insulation. "The ends of the wires are next jwhichremoves the insulatioh'fromthe ends, of

- the wires ar the wires. The ends of insulation remaining on e then subjected toa douche orspray ofshllac or like material fro'm'the tanks 15.

After the wires have been conveyed past the coating tank, the clampingmeans 1.8 may be removed, with thewiresen'gaged therein or the;

.lengths of the wires desired. This may be done by in'sertingadditional leaves of sheet metal or a "the like-forming the plane surface of the table. My invention also contemplates treating the] circumferential sections of the insulation around tion. r i i j The table maybe so constructed as to be adjustableto different widths depending upon the Other parts of the machine may likewise be'made adjustable.- The burning means may be a nar-,

row sheet of flame produced by a combustible ,gas, electrical or other'heat producing means.

The shaft 21, driven by the belt C, in turn operates and driveslthe stripping means mecha-' nism 14, by the gear chain 22, and also operates the conveyor 25. This conveyor carries the clamping or retaining means 18 to the operators on the opposite side of the table'in the di-v rection indicated by the arrow in Figure 1.,

I ,claim: 1

1. In the process of removing combustible'insulation fromconductor wires, the, steps which comprise clamping a multiplicity of the wires in spaced relation, passing the wires transversely of their length through a heated zone of sumciently high temperature toburn circumferential sections of the insulation around the'wires, and stripping the insulation from the ends of the wires.

2. In the process of removing combustible in sulation from conductor wires, the steps which comprise clamping a multiplicity of the wires in spaced relation, passing the wires transversely of 'their length through a heated zone of sufiiciently high temperature to burn circumferential sections of the insulation around the wires, strip- 129 ping the insulation from the ends. of the wires, and applying a coating material to the ends of the unremoved insulation.

. 3. Inthe process ofjremoving combustible sulation from conductor, wires, the steps which 126 comprise drawing a multiplicity of thewires spaced relationover a substantially plane surface, clamping the multiplicity. of wires in said spaced relation, cutting the wires into predetermined lengths, passing the wires transversely of 1a.

their length through. a heated zone of sufliciently high temperature to burn circumferential sec-. tions of the insulation around the wires and stripping the insulation from the ends of the wires.

4. In the process of removing combustible in-. sulation material from conductor wires, the steps which comprise drawing a multiplicity of the wires in spaced relation over. a substantially" plane surface, clamping the multiplicity of wires in said spaced relation, cutting the wires into predetermined lengths, passingthe ends of the wires transverselyof their length througha heated zone of sumciently high temperature to burn the wires, stripping the insulation from the groove to the ends of the wires from the wires and applying a coating material to theendsof the unremoved insulation. Y r

5.,In the process of removingfcombustible in- 150 sulation material from conductor wires, the steps which comprise drawing a multiplicity of wires through a coating solution and on to a substantially plane surface, clamping the multiplicity of wires in said spaced relation cutting the wires into predetermined lengths, passing the wires transversely of their length through a heated zone of sufliciently high temperature to burn circumferential sections of the insulation around the wires, and stripping the insulation from the ends of the wires.

6. In a wire stripping machine, a carriage wire clamp, a stationary wire clamp for engaging a multiplicity of wires, means for moving the .car-

riage clamp, shearing means on the stationary clamp, means for releasing the clamp, and means for conveying the clamps in a substantial horizontal plane, means for burning substantially circumferential sections of the insulation near the ends of the wires, and means for removing the insulation from said ends. 7. In a wire stripping machine, a table, clam for engaging a multiplicity of insulation wires, a conveyor means for the clamps, means for burning substantially circumferential sections of the insulation material, and stripping means for removing the insulation, from the ends of the wires. v

8. In a wire stripping machineja table, clamps for engaging a multiplicity of insulation wires,

means for conveying the clamps and wires across the surface of the table, means in the path of the,

wires for burning substantially circumferential sections about the wires near their ends, stripping means for removing the insulation from the ends of the wires, and means for coating the ends of the insulation remaining on the wires.

-9. In a wire stripping machine,:a surface or.

table, clamps engaging a multiplicity of wires and adapted to engage a groove near each end WALTER s. ROTHIERHAVM; 

